The Lockheed Martin F-35 LIGHTNING II fighter aircraft fleet recently exceeded 100.000 flight hours. At the same time the F-35 Integrated Test Force teams are completing the remaining requirements in the program’s System Development and Demonstration (SDD) phase. The remaining development flight testing includes validating the final release of 3F software, F35B ski jump testing, F-35B austere site operations, high-Mach loads testing for both the F-35B and F-35C and completion of the remaining weapons delivery accuracy tests. Lockheed Martin and Pentagon aim at completing air vehicle and mission systems software development by the end of 2017. Major SDD fleet test milestones in recent months include:

- Testing the F-35A’s final envelope involving high risk "edge of the envelope" maneuvers

- Stressing the aircraft to its limits in structural strength, vehicle systems performance and aerodynamics

- Completing all U.K. Weapon Delivery Accuracy tests for the AIM-132 ASRAAM and Paveway IV weapons

- Completing 45 of 50 SDD Weapon Delivery Accuracy tests including multiple target and multiple shot engagements as well as internal gun and centerline external pod 25 mm gun accuracy tests

- Performing multi-ship mission effectiveness tests, such as Offensive Counter-Air and Maritime Interdiction